1. Technical Field
This invention relates generally to reproduction apparatus such as copiers and/or printers, and more particularly to the collection of data about the process and to the use of data drifts to predict incipient problems before failure occurs so as to functionally optimize the reproduction apparatus.
2. Background Art
Reproduction apparatus such as for example electrophotographic copiers and printers commonly include systems for monitoring various process parameters such as paper feed timing, temperatures, availability of consumables, etc. When a parameter exceeds its set point, the apparatus may be shut down for repairs, or, if the parameter is not critical to continued operation, an operator may be alerted to the need for maintenance or other action.
Reproduction apparatus is available wherein the apparatus itself triggers a call for service to a remote interactive center whenever a serious shutdown occurs which requires the attention of a repair person. Such apparatus is also able to record the number of occurrences of less serious shutdowns which can be serviced by an on-site key operator. The apparatus triggers a call for service when a predetermined number of these less serious shutdowns have been recorded. However, there is no system available for reproduction apparatus wherein pending change or failure is anticipated by real time statistical analysis of collected data.
3. Disclosure of Invention
It is an object of the present invention to provide real time information upon which the reproduction apparatus process corrections can be based by informing operators and others (either on site or off site) that some aspect of the process is drifting out of control before the apparatus actually malfunctions or produces unacceptable results.
It is another object of the present invention to provide real time statistical process control techniques to the operation of reproduction apparatus to detect incipient change or failure of the apparatus.
It is yet another object of the present invention to provide real time statistical process control techniques to the operation of reproduction apparatus such that a predetermined change in the standard deviation of data from a sensor will provide a signal that a change or failure is incipient.
It is another object of the present invention to provide real time statistical process control techniques to the operation of reproduction apparatus such that a predetermined statistical change of data from a sensor will provide a signal that a change or failure is incipient.
It is still another object of the present invention to provide real time statistical process control techniques to the operation of reproduction apparatus to detect incipient failure(s) of the apparatus and to provide for an automatic adjustment to return statistical stability to the apparatus.
It is another object of the present invention to provide real time statistical process control techniques to the operation of reproduction apparatus to detect a need of, and to provide for, automatic adjustment to return statistical stability to the apparatus; and to provide an indication that such automatic adjustment has been effected with sufficient frequency to indicate that failure beyond that which can be accommodated by automatic adjustment is incipient.
It is another object of the present invention to provide real time statistical process control techniques to the operation of reproduction apparatus to detect a need of, and to provide for, automatic adjustment to return statistical stability to the apparatus; and to provide for more frequent sampling as the number of such adjustments grows.
It is another object of the invention to provide for real time data acquisition, communication, analysis, and hardware for accomplishing the above objects.
In accordance with a preferred embodiment of the present invention, document reproduction apparatus includes a plurality of sensors for acquiring real time diagnostic data and means for comparing the acquired data to predetermined set points; statistical or otherwise. Operation of the document reproduction apparatus is functionally optimized in response to differences between the acquired data and the predetermined set points. The optimizing operation may be in response to detection that the acquired data is tending away from nominal by studying real time statistical variations in the data, or that the acquired data is tending away from nominal by comparing real time statistical deviations in the data to a reference value or values.
The invention and its objects and advantages, will become more apparent in the detailed description of the preferred embodiments presented below.